package org.openmore.platform.utils.wechatUtils;

import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Component;

@Component
public class EmojiFilter {

        public boolean containsEmoji(String source) {
            int len = source.length();
            boolean isEmoji = false;
            for (int i = 0; i < len; i++) {
                char hs = source.charAt(i);
                if (0xd800 <= hs && hs <= 0xdbff) {
                    if (source.length() > 1) {
                        char ls = source.charAt(i + 1);
                        int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;
                        if (0x1d000 <= uc && uc <= 0x1f77f) {
                            return true;
                        }
                    }
                } else {
                    // non surrogate
                    if (0x2100 <= hs && hs <= 0x27ff && hs != 0x263b) {
                        return true;
                    } else if (0x2B05 <= hs && hs <= 0x2b07) {
                        return true;
                    } else if (0x2934 <= hs && hs <= 0x2935) {
                        return true;
                    } else if (0x3297 <= hs && hs <= 0x3299) {
                        return true;
                    } else if (hs == 0xa9 || hs == 0xae || hs == 0x303d
                            || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c
                            || hs == 0x2b1b || hs == 0x2b50 || hs == 0x231a) {
                        return true;
                    }
                    if (!isEmoji && source.length() > 1 && i < source.length() - 1) {
                        char ls = source.charAt(i + 1);
                        if (ls == 0x20e3) {
                            return true;
                        }
                    }
                }
            }
            return isEmoji;
        }

        private boolean isEmojiCharacter(char codePoint) {
            return (codePoint == 0x0) || (codePoint == 0x9) || (codePoint == 0xA)
                    || (codePoint == 0xD)
                    || ((codePoint >= 0x20) && (codePoint <= 0xD7FF))
                    || ((codePoint >= 0xE000) && (codePoint <= 0xFFFD))
                    || ((codePoint >= 0x10000) && (codePoint <= 0x10FFFF));
        }

        /**
         * 过滤emoji 或者 其他非文字类型的字符
         *
         * @param source
         * @return
         */
        public String filterEmoji(String source) {
            if (StringUtils.isBlank(source)) {
                return source;
            }
            StringBuilder buf = null;
            int len = source.length();
            for (int i = 0; i < len; i++) {
                char codePoint = source.charAt(i);
                if (isEmojiCharacter(codePoint)) {
                    if (buf == null) {
                        buf = new StringBuilder(source.length());
                    }
                    buf.append(codePoint);
                }
            }
            if (buf == null) {
                return source;
            } else {
                if (buf.length() == len) {
                    buf = null;
                    return source;
                } else {
                    return buf.toString();
                }
            }
        }
    }
